Hen nesting apparatus and brood control method

ABSTRACT

Nesting apparatus (2) for hens includes a line of nesting cages (2), and an ejector member (4) in each cage (2), individually actuatable independently of the ejector members (4) in the other cages (2) to eject a hen from the respective cage (2) upon the existence of one or more specified conditions, such as the laying of an egg in the cage (2), the occupation of the cage (2) by the respective hen a predetermined length of time, etc. The hens carry transponders (15) which may be interrogated by a reader (18) movable along the line of cages (2) to identify the hens and to keep track of their activities.

FIELD AND BACKGROUND OF THE INVENTION

The present invention relates to hen nesting apparatus, and also to amethod for utilizing such apparatus for broody (nesting) control andother controls of hens according to criteria applicable to individualhens. The invention is particularly (but not exclusively) useful withrespect to turkey hens and is therefore described below in connectionwith this application.

Nesting apparatus is known, e,g., as described in Israel Patent 52211(U.S. Pat. No. 4,188,911), for turkey hens which include a line ofnesting cages and an ejector assembly in each cage actuatable to eject ahen from the cage. In these known constructions, the ejector assembliesof all the cages are actuated at the same times according to fixedintervals (e.g., at 45-minute intervals). Such constructions thereforedo not maximize the use of the nesting cages. Moreover, the currentmethods of broody control generally deal with the flocks as a whole, andtherefore do not maximize the egg output of the individual hens within aflock.

OBJECTS AND BRIEF SUMMARY OF THE INVENTION

An object of the present invention is to provide nesting apparatushaving advantages in the above respects.

Another object of the invention is to provide nesting apparatus, andalso a method of utilizing such apparatus, for controlling the broodingof a flock of hens in order to maximize their egg output.

According to a one aspect of the present invention, there is providednesting apparatus for hens, comprising: a line of nesting cages; and anejector system including an ejector member in each cage actuatable toeject a hen therefrom; the ejector member in each cage including anindividual actuator enabling the ejector member to be individuallyactuated independently of the ejector members in the other cages toeject a hen from the respective cage.

According to another aspect of the invention, there is provided nestingapparatus for hens, comprising: a transponder attachable to each heneffective, upon being interrogated by an antenna, to transmit a signalidentifying the respective hen; a line of nesting cages; a carriagemovable along a path traversing the line of cages; a carriage drive fordriving the carriage; an encoder for continuously indicating theinstantaneous position of the carriage with respect to the cagestraversed by the carriage; an antenna carried by the carriage forinterrogating the transponders carried by the hens in the cages as thecages are traversed by the carriage; and a receiver for receiving thesignals from the transponder and for thereby identifying the hens in thecages as traversed by the carriage.

According to a still further aspect of the invention, there is provideda method of controlling a flock of hens, comprising: providing the flockof hens with a line of nesting cages each including an ejector memberactuatable to eject a hen therefrom; sensing the occurrence of aspecified condition with respect to individual hens; and controlling theejector assembly of a nesting cage occupied by a hen in response tosensing the occurrence of the specified condition with respect to therespective hen. There may be one or more specified conditions, includingthe laying of an egg by the same hen during a predetermined time period(e.g., 24 hours), the entry of the hen a predetermined number of timesin a cage within a predetermined time period, the time spent by the henin a cage, the time of day the respective hen entered the cage, and/orthe time of day when the hen laid the previous egg.

According to a still further aspect of the invention, there is provideda method of controlling a flock of hens comprising: attaching to eachhen a transponder effective, upon being interrogated, to transmitsignals identifying the respective hen; moving an antenna along a lineof the nesting cages for interrogating the transponders carried by thehens in the cages; receiving identification signals from thetransponders as they are interrogated by the antenna; and determiningthe instantaneous position of an antenna at the time a signal isreceived from an interrogated transponder to thereby identify the hen ineach cage occupied by a hen.

As will be described more particularly below, the apparatus and methodof the present invention enable each hen of a flock to be individuallyidentified and its activity individually tracked, and also enable eachcage to be individually controlled to produce a maximum egg output fromthe hens.

Further features and advantages of the invention will be apparent fromthe description below.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is herein described, by way of example only, withreference to the accompanying drawings, wherein:

FIG. 1 is a top plan view illustrating one form of nesting apparatusconstructed in accordance with the present invention;

FIG. 2 is an enlarged perspective view of a portion of the apparatus ofFIG. 1 from the egg conveyor side of the apparatus;

FIG. 3 is a perspective view of a portion of the apparatus of FIG. 1from the side opposite to that of the egg conveyor;

FIG. 4 is a perspective view of another portion of the apparatus fromthe same side as in FIG. 3;

FIG. 5 is an enlarged perspective view of a portion of the Apparatusseen in FIG. 4;

FIG. 6 is an exploded view illustrating a slip-coupling used in theportion of the apparatus shown in FIGS. 4 and 5;

FIG. 7 is a perspective view illustrating a plurality of the cages andparticularly the ejector assembly of one of the cages in itsnon-actuated condition;

FIG. 8 is a view similar to that of FIG. 6 but showing the ejectorassembly in its actuated condition;

FIG. 9 is a perspective view more particularly illustrating the mainelements of the ejector actuator system;

FIGS. 10-13, respectively, are side elevational views illustratingdifferent phases of the operation of the ejector assembly and itsactuator system;

FIG. 14 illustrates the transponder;

FIG. 15 illustrates the manner of attachment of the transponder to ahen;

FIG. 16 is a block diagram schematically illustrating the overallelectrical control system;

FIG. 17 is a side elevational view, corresponding to that of FIG. 10,but illustrating a modification in the construction of the apparatus;and

FIG. 18 is an enlarged view of the egg flagging arrangement included inthe apparatus of FIG. 17.

DESCRIPTION OF A PREFERRED EMBODIMENT Overall Construction

The nesting apparatus shown in FIGS. 1-16 illustrates a preferredembodiment of the invention to enable the brooding of a flock of hens,particularly turkey hens, to be efficiently managed in order to producea maximum yield of eggs. For this purpose, the apparatus includes a lineof nesting cages 2 for the hens to shelter them from disturbances at thetime of nesting. As shown particularly in FIGS. 10-13, each cageincludes a trap 3 which is normally open and automatically closes when ahen enters the cage, and an ejector member in the form of a bar 4 whichis actuated in order to gently eject the hen from the cage so as topermit the cage to be used for other hens. All the ejector bars 4 in theline of cages 2 are actuated by a common drive shaft 5 which is rotatedin one direction by the forward movement of a pneumatic piston-cylinderdrive 6 (FIG. 1), and rotated in the return direction by the returnmovement of the piston-cylinder drive.

As shown in FIG. 1, the eggs are collected from all the cages 2 by aconveyor belt 7 which extends along one side of the line of nestingcages 2. The conveyor belt 7 is driven by a motor 8 carried by a base 9at one end of the apparatus so that the conveyor belt traverses the lineof cages 2 in order to receive the eggs and to convey them to acollection table 10. The cages 2 are defined by a plurality of partitionplates 11 mounted to a frame structure 12. The drive shaft 5 isrotatably supported by the frame structure to overlie the upper ends ofall the cages 2.

The nesting apparatus, insofar as described above, is well known, asshown for example in the above-cited patent, and is in wide commercialuse. Further details of the construction and operation of such a knownnesting apparatus are therefore not set forth herein.

The nesting apparatus illustrated in the drawings includes a number ofnovel features over the known apparatus to enable flocks of hens to bemore efficiently managed in order to produce a maximum egg yield.

One important feature of the illustrated apparatus is that, whereas inthe previously known apparatus the ejector members for all the cageswere actuated at the same time, in the apparatus illustrated herein, andto be described more particularly below, the ejector member of each cageis individually controlled to enable the ejector member of a particularcage to be individually actuated independently of those of the othercages when an egg has been laid in the respective cage, and/or whenanother specified condition with respect to a particular hen hasoccurred.

Another important feature is that the illustrated apparatus enables allthe movement of the hens to be monitored, particularly when in one ofthe nesting cages, to enable records to be maintained of the number ofeggs laid by any particular hen. For this purpose, each hen is providedwith a transponder, generally designated 15 (FIGS. 14, 15), attached toa retaining band 16 applied to a leg of the hen. Each transponderincludes an identification of the respective hen and cooperates with areader 18 (e.g., FIG. 10) carrying an antenna 19 which traverses theline of nesting cages in close proximity to the transponders 15 of thehens within the cages. The reader 18 interrogates the transponders insequence by transmitting a power burst via an antenna. The power burstcharges each transponder and enables it to transmit a return signal thatcarries the hen identification and/or other data stored in it for therespective hen.

An example of a transponder/reader system that may be used is thatsupplied by Texas Instruments under the trademark "TIRIS"; it is basedon a low-frequency FM transmission techniques.

The Egg Sensors

As shown particularly in FIGS. 10-13, the bottom 20 of each cage 2 isinclined downwardly towards the egg conveyor 7 so that any egg laid inthe respective cage moves by gravity onto the conveyor 7. The eggconveyor 7 is supported by a frame member 21 below the respective end ofthe cage bottom wall 20.

As shown in FIG. 2, an egg sensor in the form of a bail-shaped member 22is pivotally mounted across the respective end of each cage, adjacent tothe egg conveyor 7 so that this member is engaged and pivotted by an eggmoving by gravity from the cage bottom wall 20 onto the egg conveyor.When a bail 22 is so pivotted by an egg moving onto the conveyor belt 7,it actuates an electrical switch 23, which thereby provides a signalthat an egg has been laid in the respective cage.

The Ejector Assemblies and Their Actuation System

Each cage is provided with an ejector assembly, which includes thepreviously-mentioned ejector bar 4, actuated when the egg sensor(electrical switch 23 actuated by bail 22) has sensed that a hen haslaid an egg in the respective cage and/or when another specifiedcondition with respect to a particular hen has occurred. In theembodiment of the invention described in FIGS. 1-16 for purposes ofexample, when the laying of an egg in a particular cage has been sensed,the ejector actuator system actuates the ejector assembly of therespective cage to eject the hen then in the cage.

As shown particularly in FIGS. 4 and 5, the common actuator system forall the ejector bars includes a carriage, generally designated 30,supported at its opposite ends by two pairs of upper rollers 31 and apair of lower rollers 32 movable along opposite sides of a guide rod 33adjacent to the upper ends of all the cages 2. Carriage 30 is driven bya closed-loop belt 34 rotated by a motor 35 supported at one end of theframe structure 12 (FIG. 3). An encoder 36 provides an electricalindication of the instantaneous position of the carriage.

Carriage 30 is coupled to the closed-loop belt 34 by a two-partslip-coupling, best seen in FIGS. 5 and 6. One part 37 is secured to thecarriage 30, e.g., as shown at 37a in FIG. 5, and includes a pair ofrollers 37b receivable within recesses 38a of the second part 38 fixedto the belt 34. Normally, rollers 37b are seated in recess 38a tothereby couple the carriage 30 to the belt 34; however, should movementof the carriage be blocked by an obstacle, rollers 37b will unseat fromrecesses 38a, to thereby prevent damage to the belt or to motor 35driving it.

Carriage 30 carries a solenoid 40 which, in this embodiment, isenergized by the actuation of one of the egg sensors (switch 23, FIG. 2)when an egg has been laid in a particular cage or when another specifiedcondition with respect to a particular hen has occurred. Solenoid 40 iscoupled to one end of a pivotal link 41. The opposite end of link 41 ispivotally coupled to a second link 42 also pivotally mounted to thecarriage 30. The two links 41, 42 are pivotally mounted at an angle toeach other such that they form an apex at their juncture 43 which is ata relatively low position when solenoid 40 is not energized, but whichis moved to a higher position when the solenoid is energized.

The apex 43 between the two links 41, 42 serves as an actuator foractuating the ejector assembly of a particular cage when a hen has laidan egg therein as sensed by the egg sensor switch 23, and/or whenanother specified condition has occurred. Thus, the ejector assembly ofeach cage includes a roller 44 projecting through an opening 45 in theapparatus frame 12. Normally, solenoid 40 is not energized, so that theapex 43 between the two links 41, 42 passes under all the rollers 44;however, when solenoid 40 is energized, apex 43 is moved upwardly toengage the next roller 44 which it encounters during its movement bycarriage across the line of cages. This actuates the ejector assembly ofthe respective cage to couple the ejector assembly to drive shaft 5, andthereby to actuate the ejector bar 4 to eject a hen from the respectivecage.

The construction of the ejector assembly for each cage is moreparticularly illustrated in FIG. 9, and its operation is described belowwith respect to FIGS. 10-13.

Thus, as shown in particularly in FIGS. 9 and 10, roller 44 is coupledto one end of a lever 46 formed with a shoulder 47. This shouldernormally seats one end 48a of a clutch bar 48 pivotally mounted to theframe such that the opposite end 48b of the clutch bar is normallyraised above a clutch segment 49 secured to the drive shaft 5. However,when roller 44 is lifted by the engagement with apex 43 of the two links41, 42, lever 46 is pivotted to permit clutch bar 48 to pivot(clockwise, FIG. 10), to bring its end 48b into alignment with clutchsegment 49 (FIG. 11), and thereby to couple the clutch bar to the driveshaft 5.

Clutch bar 48 is pivotally mounted at 48c to an ejector frame 50 suchthat when the clutch bar is coupled to drive shaft 5 it pivots theejector frame. The latter frame pivotally mounts ejector bar 4 and alsotrap 3. The arrangement is such that when the ejector frame 50 ispivotted in a clockwise direction, as shown in FIGS. 11-13, it moves theejector bar 4 towards the entrance of the respective cage to eject thehen therefrom and at the same time moves the trap 3 to its open positionto thereby permit another hen to enter. During the return movement ofdrive shaft 5, it returns the ejector bar 4 to its initial position, andthe clutch bar 48 is relatched in its normal position with its end 48aseated against shoulder 47 and lever 46, assuming that its roller 44 hasreturned to its lower position.

The cage from which a hen has been ejected is thus open to enableanother hen to enter. When another hen does enter, it closes trap 3 toprevent another hen from entering.

As trap 3 is closed by the entry of a hen into a cage, it may be latchedin its closed position to prevent the hen from exiting until the ejectorassembly of the respective cage has been actuated. Thus, the ejectorassembly of each cage may include a latching member 51, in the form of abail pivotally mounted to the ejector frame 50 at one end 51a, andcooperable at its opposite end with an extension 52 in trap 3. Thus, asshown particularly in FIGS. 7 and 10, when trap 3 is closed, latchingbail 51 engages the upper end of the trap extension 52 to therebyprevent the trap from being opened by the hen; but as soon as theejector assembly of the respective cage has been actuated, latching bail51 is pivotted out of engagement with the end of trap extension 52, topermit the trap to be opened at the time the ejector bar 4 is actuated,as shown in FIGS. 12 and 13.

The apparatus frame 12 further includes a second series of openings 55(FIG. 4) one for each cage 2. These openings are cooperable with anoptical detector (not shown) carried by reader 18 for calibratingpurposes. Thus, encoder 36, which identifies the position of thecarriage 30 with respect to the cages 2, may be pre-calibrated byopenings 55 at known locations with respect to each of the cages.

Control Circuit (FIG. 16)

The control circuit included in the apparatus is schematicallyillustrated in FIG. 16. It includes a microprocessor or controller 60having a number of inputs, including the following: the input treatmentcriteria 61, specifying the conditions or other criteria governing thetreatment of the hens; the egg sensor switches 23 for all the cages 2;the transponder reader 18, including its antenna 19; encoder 36 toindicate the instantaneous position of the carriage 30; and a timer 62.In response to the foregoing inputs, microprocessor 60 outputs controlsignals to control the following operations: drive motor 8for the eggconveyor 7; drive motor 35 for the carriage 30; the piston/cylinderdrive 6 for the drive shaft 5; and solenoid 40 carried by carriage 30for actuating the ejector assembly of a cage in which the laying of anegg has been sensed.

In addition, microprocessor 60 outputs at 63 various types of data forindividual hens that may be used for efficiently managing the flock ofhens, as will be described more particularly below; this data istherefore returned as an input to the microprocessor.

Overall Operation

The apparatus would be initially conditioned as shown in FIG. 13,wherein the traps 3 for all the cages 2 are in their open positions topermit the entry of a hen in each cage. Whenever a hen enters a cage, itcloses trap 3 of the cage. As soon as the cage trap 3 is closed, it islatched in its closed condition by latching bail 51 engaging the end ofextension 52 of trap 3 (FIG. 10), thereby preventing the hen fromexiting the cage.

The hens may thus freely enter the cages for nesting purposes, but areprevented from exiting from the cage until the ejector assembly of therespective cage has been actuated.

Motor 35 continuously drives carriage 30 back and forth across the lineof cages. Normally, solenoid 40 is not energized, so that the actuatorapex 43 between links 41, 42 is below the rollers 44 of the ejectorassemblies for all the cages, and therefore none of the ejectorassemblies is coupled to the drive shaft 5.

Drive shaft 5 is rotated as required, e.g., periodically every tenminutes, first in one direction and then in the opposite direction, bypiston-cylinder drive 6. In the initial, normal condition of the ejectorassemblies, none of the ejector assemblies is coupled to the driveshaft, and therefore none is actuated by it during the periodicactuations of the drive shaft.

Whenever a hen in a cage lays an egg, the downwardly-inclined bottomwall 20 of the cage causes the egg to move by gravity onto the eggconveyor 7. During this movement of the egg, it engages bail 22 (FIG. 2)for the respective cage, and thereby actuates the egg sensor switch 23of the respective cage. This information is fed to the controller 60,thereby enabling the controller to identify in which cage an egg hasbeen laid as soon as the egg passes onto the egg conveyor 7.

Controller 60, via the carriage conveyor encoder 36, can also identifythe instantaneous position of the carriage 30. As soon as the carriageapproaches a cage in which an egg has been laid or when anotherspecified condition with respect to a particular hen has occurred,solenoid 40 of carriage 30 is energized: this raises the apex 43 betweenthe two links 41, 42, to engage roller 44 of the ejector assembly in therespective cage. The engagement of roller 44 by apex 43 of the actuatorassembly pivots the roller upwardly to cause lever 46 to release the end48a of clutch bar 40, and thereby to permit the opposite end 48b of theclutch bar to drop into engagement with clutch segment 49 carried bydrive shaft 5, as shown in FIGS. 10 and 11, respectively. The nextrotation of the drive shaft 5 will therefore actuate the ejectormechanism for the respective cage. When the ejector mechanism has beenso actuated, it pivots latching bail 51 to its releasing position, outof engagement with the end of latching extension 52 of the cage trap 3.It also drives ejector bar 4 towards the entrance to the respectivecage, thereby gently ejecting the hen therefrom; and further, it movesthe trap 3 to its open position, as seen in FIG. 13, to permit anotherhen to subsequently enter the cage. The return rotation of drive shaft 5returns ejector bar 4 to its initial position while the trap 3 remainsopen.

Modifications Illustrated in FIGS. 17 and 18

FIGS. 17 and 18 illustrate several possible modifications in theapparatus.

According to one modification, the eggs are not removed from the cagesby gravity, but rather by an egg-remover plate 100 pivotally mounted atthe lower end of ejector bar 4, similar to the construction described inthe above-cited U.S. Pat. No. 4,188,911. Accordingly, the egg conveyorbelt (7, FIG. 1) is located opposite to the hen entry/exit side of thecage where it is supported by a frame member 102.

Another modification illustrated in FIGS. 17 and 18 is that the movementof an egg from the cage onto the conveyor belt 7 is sensed by a flag 104which is biassed by a spring 106 to one of two stable positions. Thus,flag 104 is normally in the broken-line position illustrated in FIG. 18,but upon the movement of an egg onto the conveyor belt 7, the flag ismoved by the egg to the actuated position shown in full lines in FIG. 18to thereby provide an indication that an egg has been laid in the cageof the respective hen. This is sensed by an electrical switch sensor 108(FIG. 17), carried by the carriage 30, which sensor also resets the flag104 to its normal condition by actuating a solenoid plunger 110 (FIG.18) to the side of the sensor.

The remainder of the structure in the apparatus illustrated in FIGS. 17and 18 is substantially the same as described above, and thereforecorresponding reference numerals have been used to identifycorresponding parts.

Efficient Management of a Flock of Hens

It will thus be seen that the apparatus illustrated in the drawingsefficiently uses the nesting cages for producing maximum egg yield byactuating the ejector mechanism of each cage, not periodically atpredetermined constant intervals as heretofore, but rather aperiodicallywhen required, e.g., shortly after the hen in a cage has laid an egg.

The illustrated system enables the egg yield from the flock to be evenfurther increased by using the transponder 15 attached to each hen formonitoring the activities of the hens particularly when in the nestingcages. Thus, this transponder permits the egg output of each hen to bemonitored since it can identify the hen in each cage where an egg hasbeen laid.

The illustrated apparatus permits even more efficient management of theflock. Thus, if it is determined that a particular hen has laid an eggwithin a preceding predetermined time interval (e.g., the preceding 24hours), the chances are that the hen will not then lay another egg evenif it entered a nesting cage; and therefore when such a hen has entereda nesting cage, the ejector assembly of the respective cage can beactuated to eject the hen immediately. In addition, if a hen hasremained in a cage for a predetermined interval (e.g., 60 minutes) andhas not yet laid an egg, the ejector assembly for the respective cagecan be actuated, thereby enabling the time allowed for each hen tooccupy a cage to be regulated individually.

The illustrated system, particularly the provision of the transpondersidentifying each hen and the eggs laid by the respective hens, permitsdata to be gathered for each individual hen or a group of hens to enablemore efficient management of the flock as a whole. For example, wherethe egg output of a particular hen is too low, this may indicate thatthe daily routine of the hen should be changed, or that the particularhen should not longer be used for egg laying purposes.

While the invention has been described above primarily with respect toone preferred embodiment, it will be appreciated that this is set forthmerely for purposes of example, and that many variations may be made.For example, instead of providing an egg sensor for each cage, a singleegg sensor may be provided at a predetermined location of the eggconveyor, and an encoder, or other means, may be used for determiningthe cage from which the egg entered the conveyor. Also, other types ofegg sensors could be used, for example optical sensors rather thanelectrical-switch sensors. Further, the egg-sensor arrangement forautomtically actuating the ejector assemblies could be used without thetransponder arrangement for monitoring all activities of the hens, andvice versa.

Further variations, modifications, and applications of the inventionwill be apparent.

I claim:
 1. Nesting apparatus for hens, comprising:a line of nestingcages; and an ejector system including an ejector assembly in each cageactuatable to eject a hen therefrom; said ejector assembly in each cageincluding an individual actuator enabling the ejector assembly to beindividually actuated independently of the ejector assemblies in; theother cages to eject a hen from the respective cage; said ejector systemincludes a common drive rotated at preset intervals for all the ejectorassemblies; said individual actuator for each ejector assembly inncludesa coupling between the ejector assembly of the respective cage and thecommon drive, normally decoupling the ejector assembly from the commondrive; and said ejector system includes a control for actuating saidcoupling to couple the ejector assembly of the respective cage to saidcommon drive.
 2. The apparatus according to claim 1, wherein said commondrive comprises:a drive shaft extending across said line of nestingcages; and a motor actuated to rotate said drive shaft and to therebyactuate all the ejector assemblies coupled thereto.
 3. The apparatusaccording to claim 1, wherein there is an egg sensor for each cageengageable by an egg to actuate the ejector assembly of the respectivecage.
 4. Nesting apparatus for hens comprising:a line of nesting cages;and an ejector system including an ejector assembly in each cageactuatable to eject a hen therefrom; said ejector assembly in each cageincluding an individual actuator enabling the ejector assemblies to beindividually actuated independently of the ejector assemblies in theother cages to eject a hen from the respective cage; a carriage movablealong a path traversing said nesting cages; a carriage drive for drivingsaid carriage; a transponder to be carried by each hen and effective,upon being interrogated by an antenna, to transmit a signal identifyingthe respective hen; an antenna carried by said carriage forinterrogating the transponders carried by the hens in the cages as thecages are traversed by the carriage; and a receiver for receiving theidentification signals transmitted by the transponders in the traversedcages.
 5. The apparatus according to claim 4, wherein said carriagedrive includes an encoder for continuously indicating the instantaneousposition of the carriage with respect to the cages traversed by thecarriage.
 6. Nesting apparatus for hens, comprising:a transponderattachable to each hen effective, upon being interrogated by an antenna,to transmit a signal identifying the respective hen; a line of nestingcages; a carriage movable along a path traversing said line of cages; acarriage drive for driving said carriage; an encoder for continuouslyindicating the instantaneous position of the carriage with respect tothe cages traversed by the carriage; an antenna carried by the carriagefor interrogating the transponders carried by the hens in the cages asthe cages are traversed by the carriage; and a receiver for receivingthe signals from the transponder and for thereby identifying the hens inthe cages as traversed by the carriage.
 7. The apparatus according toclaim 6, wherein said apparatus further comprises:an egg conveyor alongthe line of the nesting cages for receiving the eggs laid by the hens inthe cages; a drive for driving said egg conveyor; and an egg sensor forsensing the movement of an egg from a cage onto said egg conveyor. 8.The apparatus according to claim 7, wherein there is an egg sensor foreach cage, each egg sensor including an electrical switch and a switchoperator engageable by an egg when passing from the respective cage tothe egg conveyor.
 9. The apparatus according to claim 7, wherein theapparatus further comprises:an ejector assembly in each cage actuatableto eject a hen therefrom; and an ejector actuator system including anactuator for each ejector assembly individually actuatable independentlyof the ejector members in the other cases to eject a hen from therespective cage.
 10. The apparatus according to claim 9, wherein saidejector actuator system includes:a common drive for all the ejectorassemblies: a coupling assembly between the ejector assembly of eachcage and the common drive, normally decoupling the ejector assembly fromthe common drive; and a control for actuating said coupling assembly tocouple the ejector assembly of the cage to said common drive.
 11. Theapparatus according to claim 10, wherein said common drive comprises:adrive shaft extending across said line of nesting cages; and a motoractuated to rotate said drive shaft and to thereby actuate all theejector assemblies coupled thereto.
 12. A method of controlling a flockof hens, comprising:providing the flock of hens with a line of nestingcages each including an ejector assembly actuatable to eject a hentherefrom; sensing the occurrence of a specified condition with respectto individual hens; said specified condition includes the sensing of thelaying of an egg by the hen in the respective cage; and controlling theejector assembly of a nesting cage occupied by a hen in response tosensing the occurrence of the specified condition with respect to therespective hen.
 13. A method of controlling a flock of hens,comprising:providing the flock of hens with a line of nesting cages eachincluding an ejector assembly actuatable to eject a hen therefrom;sensing the occurrence of a specified condition with respect toindividual hens; and controlling the ejector assembly of a nesting cageoccupied by a hen in response to sensing the occurrence of the specifiedcondition with respect to the respective hen; wherein the ejectorassemblies are actuated by a common drive, said ejector assemblies beingnormally uncoupled to said common drive but being coupled thereto uponthe sensing of the specified condition with respect to the hen in therespective cage.
 14. A method of controlling a flock of hens,comprising:providing the flock of hens with a line of nesting cages eachincluding an ejector assembly actuatable to eject a hen therefrom;sensing the occurrence of a specified condition with respect toindividual hens; controlling the ejector assembly of a nesting cageoccupied by a hen in response to sensing the occurrence of the specifiedcondition with respect to the respective hen; attaching to each hen atransponder effective, upon being interrogated, to transmit a signalidentifying the respective hen; moving an antenna along the line ofnesting cages for interrogating the transponders carried by the hens inthe cages; receiving identification signals from the transponders asthey are interrogated by the antenna; determining the instantaneousposition of an antenna at the time a signal is received from aninterrogated transponder, to thereby identify the hen in each cageoccupied by a hen; and upon determining that a hen in a particular cagehas already laid an egg in one of the cages within a predetermined timeperiod, actuating said ejector assembly to eject the hen from therespective cage.
 15. A method of controlling of a flock of hens,comprising:moving an antenna along a line of the nesting cages forinterrogating the transponders carried by the hens in the cages;receiving identification signals from the transponders as they areinterrogated by the antenna; and determining the instantaneous positionof an antenna at the time a signal is received from an interrogatedtransponder to thereby identify the hen in each cage occupied by a hen.16. The method according to claim 15, wherein the instantaneous positionof the antenna at the time a signal is received from an interrogatortransponder is determined by an encoder coupled to a drive moving theantenna along the line of nesting cages.
 17. The method according toclaim 15, wherein the laying of an egg by a hen in a cage is sensed, andan ejector mechanism is actuated in response thereto for ejecting thehen from the respective cage.